Center-grinder



I 3 Sheets-Sheet 2.

(No Model.)

0. H. NORTON. CENTER GRINDER.

No. 496,891. Patented May 9, 189 3..

WITNESSES TM: Noam PETERS e0. PrioToLmw.v WASHINGTON. D. c.

(No Model.) I 3 Sheets-Shet 3.

G.- H. NORTON. CENTER GRINDER.

No 496,891; Patented May 9, 1893.

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gag 553,. wad/m UNITED STATES PATENT OFFICE.

CHARLES H. NORTON, OFDETROIT, MICHIGAN.

CENTER-GRINDER.

SPECIFICATION forming part of Letters Patent No. 496,891, dated May 9,1893.

Application filed February 23, 1892. Serial No. 422,385- (No model.)

To aZZ whom it may concern.-

Be it known that 1, CHARLES H. NORTON, a citizen of the United States,residing at Detroit, county of Wayne, State of Michigan, have invented acertain new and useful Improvement in Center-Grinders; and I declare thefollowing to be a full, clear, and exact description of the invention,such as will enable others skilled in the art to which it pertains tomake and use the same, reference being bad to the accompanying drawings,which form a part of this specification.

This invention relates to center grinders, machines for grinding andtruing the center projecting from the stock of a lathe, and isespecially intended to provide an improved means or tool adapted to bemounted on the ordinary tool holding slide of a lathe, and to accuratelypoint at the true center of revolution of the face-plate or revolvingcenter piece, the holding part usually known as the center. Toaccomplish the desired result I employ, the tool shown in theaccompanying drawings, in which- Figure 1 is a plan view of the tool inposition between the centers of the head and tail stock. Fig. 2 is ahorizontal central section through the tool. Fig. 3 is a frontelevation.

A represents the center connected to the head stock, and B, the centerconnected to the tail stock of an ordinary lathe.

0, represents the sliding tool holder, with the ordinary tool holdingpost 0.

D, represents what I call the locating holder of the tool. It consistsof a bar provided with conical cavities at the ends 01, cl, adapted tobe placed between the centers A, and B, and to be held in the samemanner that a bar is held between them when the lathe is in use. Acrossthe bar at an angle, is a holding arm d perforated and fitted with abushing (1 The bushing d lies across the line between at and d, at anangle and the acute angle between the intersecting axes of the twobranches, is equal to one-half the angle to which it is desired tofinish the point A.

Within the bushing (Z is a sleeve journal E, attached at its inner endto the interior of the elongated hub H, of a pinion h, adapted to turnwith the journal E. The inner end (1 of the bushing (1 extends beyondthe walls of the branch (Z and is received within .the hub H of thepinion h, and outside of the journal E, thus providing a housing ofconsiderable length adapted to permit the parts to move endwise withrespect to one anotherthrough aconsiderable distance, and at the sametime to prevent dust or particles of steel or iron from reaching thebearing between the journal E, and the bushing d within which it turns.

Through the sleeve journal E, passes the stem or spindle e, on the-innerend of which is mounted an emery wheel W; the emery wheel W, is heldbetween the clamping faces of a hub w, and a holding nut w., The hub w,has a long annular extension telescoping over the hub H, adapted tofurnish a guard similar to the one previously described, to pre ventdust from entering around the inner end of the hub H. In the spindle e,are two key ways on opposite sides of the middle line, and into the keyways k, k, project feathers or keys K, K, from the sleeve journal E. Ahandle H is attached to the end of the spindle e. The constructiondescribed allows the wheel W to be shifted or moved parallel with Vitself through a short distan'ce,while the pinion h, is in motion andthewheel W, to which it is connected is atwork.

A working holder L, is adapted to be received within the ordinary toolholding post of the slide rest. The working holder L, is firmlyconnected to thelocating holder D, and the relativepositions of the twoare constant. At the inner end of the working holder L, is a cross armZ, bored out to receive the spindle of the beveled gear I), which isarranged to mesh with the pinion h. The spindle b of the beveled gearwheel I), on the end remote from the gear wheel I), is connected by auniversal joint J, with a driving shaft S. The driving shaft S issupported by a movable hanger T, that slides or is capable of sliding onan arm V. The arm V, springs from a hanging arm V, that is hinged at '0,to the main or body part of the tool; the axis of the hinge o, is inline with and above the center of the joint J, and consequently theholding arm V, and the driving shaft S, can both of them be moved in anare around the axial line passing through the hinge o, and thejoint Jand the hanger T, can be moved along the arm V, and along-the drivingshaft S, either f, projecting into a long key way and thus while thewheel itself can be moved endwise with the hanger T, it compels theshaft S to rotate with it whenever it is itself rotated. To employ thiscenter grinder the setting holder D, is placed between the centers ofthe lathe, and the working holder L, in the tool holding post of theordinary slide rest, and the tool is made fast in position like anyordinary tool; the slide rest is then moved until the setting holder D,is away from the points to be ground. The use of the setting holder D,and the working holder L in unison adjusts the shaft of the grindingwheel W, at the proper angle with respect to the center to be ground;the subsequent movement of the slide rest does not change this angle,butby the use of the slide rest the setting holder D may be moved out ofthe way, and the grinding wheel W moved up into contact with the center,and its grinding edge will lie parallel to the edge of the coned surfaceof the center, and can be pressed into contact with any degree of forcedesired by the use of the slide rest, also while the grinding wheel W,is revolving it can be moved along the coned surface from apex to baseby moving the spindle e, on the end of which the grinding wheel ismounted through the hollow journal E. The grinding wheel W, is set inmotion of revolution by means of the pinion H, and gear wheel b, theshaft S, and the friction wheel F, the friction wheel F, receiving itsmotion from contact with one of the faces of the coned pulley of thelathe. The object of the hinge at o, and J, is to permit the frictionwheel to be pressed against the cone pulley of the lathe.

The various adjustments of which the tool is capable permit of the useof the same grinding tool, with different lathes in which the conepulleys may be of different sizes or the centers and cone pulleys atdifferent distances.

What I claim is- 1. In a tool for grinding lathe centers, the

combination of a setting holder, a working holder fixed with respect toeach other; a grinding wheel having its axis of revolution fixed withrespect to said holders and means for giving motion to said grindingwheel, substantially as and for the purpose described.

2. In a tool for grinding lathe centers, the combination of a workingholder, a grinder frame supported thereby a bushing projecting beyondthe framework, a hollow journal within said bushing, a spindletraversing the hollow journal, splined thereto provided with a grindingwheel at one end, and a handle at the other end, a housing secured toone of said parts,-and telescoping over another of said parts,substantially as and for the purpose specified.

3. In a tool for grinding lathe centers the combination of a workingholder, a grinding wheel. movable lengthwise of its axis,ahingedsupporting arm provided with a handle, a friction driving wheelsupported on and adjustable lengthwise of its shaft, a sliding hangeruniting the hinged supporting arm and the shaft of the driving wheel,jointed shafting intermediate the driving wheel and the grinding wheel,substantially as and for the purpose specified.

4.. In a tool for grinding lathe centers, the combination of a workingholder, a grinding wheel, a hinged arm provided with a handle, aswinging shaft supportinga driving friction wheel, a sliding hangeruniting the arm and the shaft, a fixed shaft jointed to said swingingshaft, substantially as and for the purpose specified.

5. In a tool for grinding lathe centers, the combination of a locatingholder and a work- 'ing holderg a grinding wheel having its axis ofrevolution at an angle of said locating holder a friction wheel adaptedto swing in an are as described, a driving shaft adapted to be driven bysaid friction wheel and connected by a universal joint, to fixedshafting, adapted to drive said grinding wheel substantially as and forthe purpose described.

In testimony whereof I sign this specification in the presence of twowitnesses.

CHARLES H. NORTON. Witnesses:

CHARLES F. BURTON, EFFIE I. CROFT.

